Successful long-term outcome of liver transplantation in late-onset lysosomal acid lipase deficiency.

Late-onset LAL deficiency, previously referred to as cholesteryl ester storage disorder, is a rare lysosomal storage disorder characterized by accumulation of cholesteryl esters. It has a heterogeneous clinical phenotype including abdominal pain, poor growth, hyperlipidemia with vascular complications and hepatosplenomegaly. End-stage liver disease may occur, but there are few reports of successful LT. There are also concerns that systemic manifestations of the disease might persist post-LT. We report a case with excellent outcome eight yr following LT. The subject was noted to have asymptomatic hepatosplenomegaly during an intercurrent illness, and LAL deficiency was confirmed with compound heterozygosity in the LIPA. Despite dietary fat restriction, he developed signs of progressive liver disease and subsequently developed hepatopulmonary syndrome. He underwent cadaveric LT at the age of nine and a half yr and recovered with prompt resolution of hepatopulmonary syndrome. Eight yr post-transplant he has normal growth, normal lipid profile, and liver and renal function tests. Liver histology showed no evidence of disease recurrence at this stage. LT in this subject resulted in an excellent functional correction of late-onset LAL deficiency.

Early and late complications after liver transplantation for propionic acidemia in children: a two centers study.

Propionic acidemia (PA) is a severe metabolic disorder with cardiac and neurologic complications and a poor quality of life. Liver transplantation (LT) was thus proposed in PA to increase enzyme activity. We studied retrospectively LT in PA in two European centers. Twelve patients underwent 17 LTs between 1991 and 2013. They developed severe, unusual and unexpected complications, with high mortality (58%). When present, the cardiomyopathy resolved and no acute metabolic decompensation occurred allowing dietary relaxation. Renal failure was present in half of the patients before LT and worsened in all of them. We suggest that cardiac and renal functions should be assessed before LT and monitored closely afterward. A renal sparing immunosuppression should be used. We speculate that some complications may be related to accumulated toxicity of the disease and that earlier LT could prevent some of these consequences. As kidney transplantation has been performed successfully in methylmalonic acidemia, a metabolic disease in the same biochemical pathway, the choice of the organ to transplant could be further discussed.

Rejection is less common in children undergoing liver transplantation for hepatoblastoma.

To compare the incidence of acute histologically proven rejection in children who have had a liver transplant for hepatoblastoma with a control group of children transplanted for biliary atresia (EHBA). A retrospective case notes based study was performed. Twenty patients were identified with hepatoblastoma who were transplanted at a single unit between 1991 and 2008. These were matched as closely as possible for age, gender, year of transplant and type of immunosuppression used to the control group transplanted for biliary atresia (n = 60). There was a significant decrease in rate of acute rejection as assessed by the rejection activity index (RAI) in the hepatoblastoma group (75% vs. 50%, respectively, p < 0.04). Chronic rejection was rare in both groups, but twice as common in the biliary atresia group. Equal levels of immunosuppression were achieved in both groups. Renal function was noted to be reduced one yr post-transplant in both groups, as previously reported. A modified immunosuppression regimen could be considered in children with hepatoblastoma undergoing liver transplantation.

Diurnal variation of phenylalanine concentrations in tyrosinaemia type 1: should we be concerned?

BACKGROUND: Tyrosinaemia type 1 (HT1) is treated with a tyrosine and phenylalanine-restricted diet, amino acids free of phenylalanine and tyrosine, and nitisinone (NTBC). Treatment guidelines recommend plasma tyrosine between 200-400 µm and phenylalanine at least >30 µm. There is little information on the diurnal variation of plasma tyrosine or phenylalanine in HT1. Low plasma phenylalanine <30 µm may be associated with poor growth and cognitive delay. The present study aimed to document diurnal variation of tyrosine and phenylalanine plasma concentrations and growth in children with HT1. METHODS: Median tyrosine and phenylalanine plasma concentrations were reviewed retrospectively over 3 years in 11 subjects (median age 4 years) with HT1. Subjects routinely collected morning fasting blood samples but afternoon nonfasted samples were taken in the clinic (<10% of samples). Growth Z-scores were calculated. RESULTS: The percentage of all plasma phenylalanine concentrations <30 µm was 8.6% and <40 µm was 13.6%. Only 2% of fasting morning phenylalanine concentrations were <30 µm, compared to 83% of nonfasting afternoon samples. All but one child had a height Z-score <0. CONCLUSIONS: Blood phenylalanine concentrations were consistently lower in the afternoon. Taking blood samples at variable time points in the day may lead to variation in interpreting dietary control. A detailed study is necessary to examine the 24-h diurnal variation of plasma phenylalanine and tyrosine in HT1. It is possible that phenylalanine concentrations may be very low for a substantive time over 24 h and the potential impact that this may have on cognitive development and growth in children is unknown.

Successful isolated liver transplantation in a child with atypical hemolytic uremic syndrome and a mutation in complement factor H.

A male infant was diagnosed with atypical hemolytic uremic syndrome (aHUS) at the age of 5.5 months. Sequencing of the gene (CFH) encoding complement factor H revealed a heterozygous mutation (c.3644G>A, p.Arg1215Gln). Despite maintenance plasmapheresis he developed recurrent episodes of aHUS and vascular access complications while maintaining stable renal function. At the age of 5 years he received an isolated split liver graft following a previously established protocol using pretransplant plasma exchange (PE) and intratransplant plasma infusion. Graft function, renal function and disease remission are preserved 2 years after transplantation. Preemptive liver transplantation prior to the development of end stage renal disease is a valuable option in the management of aHUS associated with CFH mutations.

Plasma microRNA levels in male and female children with cystic fibrosis.

A gender gap exists in cystic fibrosis (CF). Here we investigate whether plasma microRNA expression profiles differ between the sexes in CF children. MicroRNA expression was quantified in paediatric CF plasma (n = 12; six females; Age range:1-6; Median Age: 3; 9 p.Phe508del homo- or heterozygotes) using TaqMan OpenArray Human miRNA Panels. Principal component analysis indicated differences in male versus female miRNA profiles. The miRNA array analysis revealed two miRNAs which were significantly increased in the female samples (miR-885-5p; fold change (FC):5.07, adjusted p value: 0.026 and miR-193a-5p; FC:2.6, adjusted p value: 0.031), although only miR-885-5p was validated as increased in females using specific qPCR assay (p < 0.0001). Gene ontology analysis of miR-885-5p validated targets identified cell migration, motility and fibrosis as processes potentially affected, with RAC1-mediated signalling featuring significantly. There is a significant increase in miR-885-5p in plasma of females versus males with CF under six years of age.

Neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) as a cause of liver disease in infants in the UK.

Citrin deficiency is a disorder with two phenotypes: neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD), and adult-onset type II citrullinaemia (CTLN2). NICCD presents in the first few weeks of life with prolonged cholestasis and metabolic abnormalities including aminoacidaemia (notably citrulline, tyrosine, threonine, arginine and methionine) and galactosuria. Symptoms resolve within the first year of life, thus making a diagnosis difficult after this time. Although patients subsequently remain generally healthy, some may develop more severe symptoms of CTLN2, characterized by neurological changes, one or more decades later. To date more than 400 cases have been reported, almost all from East Asia (mainly Japan). Here we describe the first two cases of NICCD in infants from the UK, one of caucasian origin and one of Pakistani origin. Both showed typical clinical and biochemical changes with a diagnosis confirmed by the presence of previously unreported mutations in the SLC25A13 gene. The presence of citrin deficiency in other ethnic groups means that NICCD needs to be considered in the diagnosis of any neonate with an unexplained cholestasis. We discuss both the difficulties in diagnosing these patients in populations where very few DNA mutations have been identified and the problems faced in the management of these patients. These findings also raise the possibility of adults with CTLN2 in whom a diagnosis has yet to be made.

British paediatric surveillance unit study of biliary atresia: outcome at 13 years.

BACKGROUND: Little information is available on contemporary, prospectively collected data on the long-term outcome of national cohorts of children with biliary atresia. OBJECTIVE: This study aimed to describe the current outcome of a national cohort of children with biliary atresia. PATIENTS AND METHODS: All 93 cases of biliary atresia in the United Kingdom and Ireland diagnosed between March 1993 and February 1995 were followed up prospectively. RESULTS: A total of 91 children underwent Kasai portoenterostomy in 15 individual centres. Only 2 centres treated more than 5 children annually. Median age at last follow-up was 12 years (range 0.25-14). Fifteen children (16%) have died: 10 after unsuccessful portoenterostomy, 1 of sepsis after successful portoenterostomy, and 4 after liver transplantation. Forty-two (45%) underwent liver transplantation at a median age of 1 year (range 0.5-9), with 90% survival. All 41 children with failed portoenterostomy (and 2 without portoenterostomy) died or underwent liver transplantation at a median age of 0.8 years (range 0.25-6.5). When the portoenterostomy was successful, 40 of 50 patients (80%) are alive without liver transplantation. The 13-year actuarial survival without liver transplantation is 43.8% overall and is better in children treated at centres that treat more than 5 cases yearly (54% vs 27.3%, P = 0.005). CONCLUSIONS: If the portoenterostomy is successful, then few children with biliary atresia will need transplantation before adolescence. Children with biliary atresia should be treated in experienced centres to maximize the chance of successful surgery.

Renal tubular function in children with tyrosinaemia type I treated with nitisinone.

BACKGROUND: Tyrosinaemia type I (TTI) is an inherited deficiency in the enzyme fumarylacetoacetate hydrolase and is frequently complicated by renal tubular dysfunction which may persist in some patients after hepatic transplantation. Nitisinone has revolutionized the management of TTI but its effect on renal tubular dysfunction has not been described in a large cohort of patients. AIMS: To document the incidence and progression of renal tubular dysfunction in children with TTI treated with nitisinone at a single centre. SUBJECTS: Twenty-one patients with TTI from a single centre were treated with nitisinone for at least 12 months. Median age at first treatment was 17 weeks (range 1 week to 27 months). Nine patients (43%) presented in acute liver failure, seven (33%) had a chronic presentation and five (24%) were detected pre-clinically. METHODS: A retrospective case analysis of plasma phosphate, urinary protein/creatinine ratio and tubular reabsorption of phosphate was performed for all patients as markers of tubular function. Renal ultrasounds were examined for evidence of nephrocalcinosis and where available, skeletal radiographs for rickets. RESULTS: All patients had biochemical evidence of renal tubular dysfunction at presentation. After nitisinone and dietary treatment were started, all three markers normalized within one year. Four children had clinical rickets at presentation (which improved), of whom one had nephrocalcinosis, which did not reverse on nitisinone. No child redeveloped tubular dysfunction after commencing nitisinone. All patients with TTI had evidence of tubular dysfunction at presentation and in all cases this resolved with nitisinone and dietary control. CONCLUSION: The tubulopathy associated with TTI is reversible.

Serum lipid and lipoprotein profile of patients with glycogen storage disease types I, III and IX.

With current dietary therapy, life expectancy in glycogen storage disease (GSD) has improved considerably and more children reach adulthood. Notwithstanding intensive dietary therapy, moderate to severe hyperlipidaemia is still observed frequently. There is limited information about the type and extent of hyperlipidaemia. We studied the lipid profile in 20 patients, aged 8-54 years, of the three (types I, III and IX) most common forms of adult GSD. Hyperlipidaemia was shown to be type-specific, affecting predominantly patients with GSD type Ia, who showed marked combined hypercholesterolaemia and hypertriglyceridaemia. By contrast, a heterogeneous distribution of HDL was found in patients with GSD I and III. There was no significant difference in Apo Al and Apo B concentrations between groups. In addition, mass measurements of the fractions of VLDL1, VLDL2 and IDL were raised in all patients with GSD Ia by comparison with all other patients with GSD. Patients with GSD type Ia have lipid concentrations and individual mass measurements that are consistent with ranges found in patients who have a significant risk of atherosclerosis. Accumulated evidence, however, suggest GSD type Ia patients do not have an increased risk of atherosclerotic cardiovascular disease (CVD) but the reason remains unknown. Intervention to reduce their lipid levels could therefore be on the basis of seeking to prevent the risk of pancreatitis rather than that of CVD.

Is serum gentamicin level a good predictor of graft injury in intestinal transplantation?

INTRODUCTION: Following intestinal transplant (SBT), the early diagnosis and treatment of rejection is a major management aim. The diagnosis of rejection is based on histology of stomal biopsies. Oral gentamycin (2.5 mg/kg) was used for selective decontamination of the digestive system. Our hypothesis was that gentamycin might be absorbed in the presence of graft dysfunction. AIM: Our goal was to assess the correlation between serum gentamycin level and the health of the intestinal graft. SUBJECTS AND METHODS: Among 33 SBT performed from 1993 to 2005, serum gentamycin levels were performed once weekly or more often when there was a suspicion of rejection. All data were analyzed retrospectively. RESULTS: Adequate trough levels were achieved for only 23 patients, six of whom had histologically proven rejection and only one did not have a raised gentamycin content. Five patients with raised levels but no rejection included two with severe intestinal ischemia and three with bowel obstruction/ileus. Four of the five patients required laparotomies. CONCLUSION: We concluded that in our study raised serum gentamycin levels were a good predictor of rejection or significant injury to the graft.

Classification and genetic features of neonatal haemochromatosis: a study of 27 affected pedigrees and molecular analysis of genes implicated in iron metabolism.

Neonatal haemochromatosis (NH) is a severe and newly recognised syndrome of uncertain aetiology, characterised by congenital cirrhosis or fulminant hepatitis and widespread tissue iron deposition. NH occurs in the context of maternal disease including viral infection, as a complication of metabolic disease in the fetus, and sporadically or recurrently, without overt cause, in sibs. Although an underlying genetic basis for NH has been suspected, no test is available for predictive analysis in at risk pregnancies. As a first step towards an understanding of the putative genetic basis for neonatal haemochromatosis, we have conducted a systematic study of the mode of transmission of this disorder in a total of 40 infants born to 27 families. We have moreover carried out a molecular analysis of candidate genes (beta(2)-microglobulin, HFE, and haem oxygenases 1 and 2) implicated in iron metabolism. No pathogenic mutations in these genes were identified that segregate consistently with the disease phenotype in multiplex pedigrees. However, excluding four pedigrees with clear evidence of maternal infection associated with NH, a pedigree showing transmission of maternal antinuclear factor and ribonucleoprotein antibodies to the affected infants, and two families with possible matrilineal inheritance of disease in maternal half sibs, a large subgroup of the affected pedigrees point to the inheritance of an autosomal recessive trait. This included 14 pedigrees with affected and unaffected infants and a single pedigree where all four affected infants were the sole offspring of consanguineous but otherwise healthy parents. We thus report three distinct patterns of disease transmission in neonatal haemochromatosis. In the differentiation of a large subgroup showing transmission of disease in a manner suggesting autosomal recessive inheritance, we also provide the basis for further genome wide studies to define chromosomal determinants of iron storage disease in the newborn.

Outcome of children with hereditary tyrosinaemia following newborn screening.

BACKGROUND: Nitisinone has transformed the management of hereditary tyrosinaemia type 1 (HT1). However, the risk of developing hepatocellular carcinoma is related to the age at which treatment is commenced. Little data on the outcome of children treated pre-emptively exist. AIM: To describe the outcome of children with HT1 treated with nitisinone following selective newborn screening (NBS) and to compare their outcome with index siblings who had presented clinically. SUBJECTS: 12 children with HT1 were detected by NBS. Seven children were screened for HT1 because of an affected sibling (n=5). Four children were detected due to raised tyrosine concentrations on routine NBS and one child was born in a country with universal NBS for HT1. OUTCOME: Nitisinone was commenced at 4 (1-52) days old. 6 children had an initial coagulopathy which resolved after 4 (1-7) days treatment. Currently at median age 8.5 (3-12.5) years all are clinically normal, with normal liver function tests and imaging. Those of school age are in normal classes but four have reported learning difficulties. Five index siblings presented clinically with acute liver failure (four) and chronic liver disease (one) at median 4 (1.5-17) months. One died of liver failure prior to nitisinone's availability. Four were treated with nitisinone; one failed to respond and underwent liver transplantation and three responded. One responder died from complications of prematurity and the remaining two have compensated liver disease. SUMMARY: Children with HT1 treated with nitisinone following NBS have an excellent outcome. CONCLUSIONS: Universal NBS for HT1 should be introduced in the UK.

Familial hepatoblastoma and APC gene mutations: renewed call for molecular research.

Recent findings have increased our understanding of the molecular mechanisms involved in the pathogenesis of hepatoblastoma and their relationship to the molecular pathology of familial adenomatous polyposis (FAP). Here, we describe hepatoblastoma in siblings who share a gene mutation for FAP inherited from their father. This observation confirms the link between these diseases and has implications for future molecular research. We also raise the question; should other members of 'at-risk' families be screened following a new diagnosis of either hepatoblastoma or FAP?

En block combined reduced-liver and small bowel transplants: from large donors to small children.

BACKGROUND: The critical shortage of size-matched donor organs for infants and small children in need of combined liver and intestinal transplantation has lead to long waiting times and a high risk of dying before transplantation. Utilizing grafts from larger donors could alleviate this problem, but using larger composite grafts in small children has been challenging and unsuccessful in the past. METHODS: We conducted a pilot study for evaluating the results of transplanting into small recipients a composite graft (reduced-size liver and whole small bowel, including duodenum and pancreas head) procured from large donors. Liver size reduction was performed ex situ using the extrahilar approach, which leaves the liver hilum untouched. Straightforward implantation of the graft was performed by simple, two-step vascular anastomoses. The preservation of the donor duodenum in continuity with the combined graft avoided the need for biliary reconstruction, thus preserving maximal bowel length for gut continuity restoration in the recipient. RESULTS: Two children, weighing 7.6 and 9.8 kg, respectively, underwent transplantation of a composite graft procured from donors weighing 35 kg. Their waiting time (68 and 97 days, respectively) was shorter compared with our previous experience with conventional techniques. Both are currently alive and well, at home and on full enteral feeds, 15 and 11 months after transplantation, respectively. CONCLUSION: This new technique has extended the range of possible donors for small candidates waiting for combined grafts and was successful in two patients. It should be considered for small recipients in the future.

Complete regression of posttransplant lymphoproliferative disease using partially HLA-matched Epstein Barr virus-specific cytotoxic T cells.

BACKGROUND: Adoptive immunotherapy with autologous and donor-derived cytotoxic T lymphocytes (CTL) has recently been used to treat Epstein Barr virus (EBV)-positive posttransplant lymphoproliferative disease (PTLD). METHODS AND RESULTS: We report complete regression of EBV-positive PTLD in an 18-month-old small bowel and liver transplant recipient after one infusion of partially human leukocyte antigen (HLA)-matched EBV-specific CTL grown ex vivo from an EBV seropositive unrelated blood donor. No infusion-related toxicity or evidence of graft-versus-host disease was observed. The tumor showed signs of regression within 1 week and EBV load in peripheral blood dropped to undetectable levels. Limiting dilution analyses (LDA) detected no EBV-specific CTL precursor (CTLp) cells before the infusion, and high numbers of CTLp at 4 hr and 24 hr post-CTL infusion. There was a reversal of the CD4/8 ratio in peripheral blood and an increase in HLA-DR positive CD8 cells. The patient has been in complete remission for 24 months. CONCLUSION: If this success is repeated in more PTLD patients, then stored CTL could be used for antiviral and antitumor therapies in immunocompromised patients.

Metabolic liver disease in the pediatric patient.

Most metabolic liver diseases that affect pediatric patients present in the neonatal period with either cholestasis or acute liver failure. Metabolic liver disease in the older child has considerable overlap with adult patients. New diagnostic methods and therapy, including liver transplantation, has radically changed the outcome of many metabolic liver diseases.